This invention relates to the manufacture of magnetic recording heads and particularly to the attachment of back-bars to core legs therein and to an improved technique therefor and an associated fixture.
Workers in the art of manufacturing magnetic digital recording heads (sliders) for certain digital recording are aware of serious difficulties associated with positioning and attaching magnetic "back-bars" between protruding core legs. It is presently conventional to use spring-applied clamping action; but this is too rough and all too often, and too easily, distorts or snaps-off the core legs (typically a few grams of pressure can do so; and the careless flick of a finger can destroy a leg). This technique requires ultra-careful handling and application of pressure while the clamp is brought into contact--moreover the clamp must be held in place while the adhesive is curing--a very delicate, near-impossible operation unless a large percentage of breakage is to be tolerated (breakage is, of course, very expensive, since the parts themselves have already had a great deal of time and money invested in them).
The present invention eliminates this potentially costly and difficult procedure by substituting a "magnetic fixture" which applies a back-bar-attracting magnetic flux through the magnetic circuit of the core legs themselves and employs magnetic flux (rather than spring tension) to attract and retain the back-bar in place for bonding. As a preferred form, I teach the use of an ordinary U-shaped permanent magnet combined with a "gapped keeper" to project this magnetic flux.